An implantable medical device (IMD) is an apparatus that during use is placed inside a living body to monitor certain physiological signals and provide therapy to an organ or tissue in response to the physiological signals. An example of an IMD is an implantable cardiac device (ICD) such as a pacemaker that stimulates the heart into a contraction if the sinus node is not properly pacing such contractions. Modem cardiac devices also perform many functions beyond that of pacing. For example, some ICDs perform defibrillation and cardioversion therapies. Other ICDs are able to select among several different pacing therapies depending upon the physiologic condition of a patient's heart.
A pacemaker device, as an example of an ICD, is typically implanted in a convenient location such as beneath a patient's skin and in the vicinity of the one or more major arteries or veins. One or more electrical leads connected to the pacemaker are typically placed on or inside the patient's heart via a convenient artery or vein. The ends of the leads are placed in contact with the inside walls or the surface of one or more chambers of the heart, depending upon the particular therapies deemed appropriate for the patient.
One or more leads are adapted to carry a current from the pacemaker to the heart tissue to stimulate the heart in one of several ways, again depending upon the particular therapy being delivered. The leads are also used for sensing the physiologic signals provided by the heart to determine when to deliver a therapeutic pulse to the heart, and the nature of the pulse, e.g., a pacing pulse or a defibrillation shock. In other types of IMDs or implantable systems, additional leads may be used for applying a pain therapy stimulus to various body areas such as the spinal column. Further, one or more catheters may be connected to the IMD to deliver drugs to various body parts for pain relief, defibrillation threshold reduction, and so forth.
Distributing a variety of leads, catheters, and medical activators about a patient's body from a single IMD is a very complex procedure. Further, many lead conductors and connections to the IMD are required in order for many electrodes to be distributed. Leads and connections are expensive and increase the overall IMD size. Further, as the number of leads extending from a central device increases, the overall system reliability is reduced.
Accordingly, it is desirable to provide a simple and cost efficient system for distributing leads and associated medical activators from an IMD to one or more body locus. In addition, it is desirable to reduce the number of components associated with an IMD and thereby improve the reliability of the IMD and the associated system. Furthermore, other desirable features and characteristics of the present invention will become apparent from the subsequent detailed description and the appended claims, taken in conjunction with the accompanying drawings and the foregoing technical field and background.